Silsilah as-Sahihah 2771 — Heresy in the Haram is a grave crime

Ishaq bin Saeed narrates from his father that Sayyiduna Abdullah bin Amr (may Allah be pleased with them) came to Sayyiduna Abdullah bin Zubair (may Allah be pleased with him) and said: Ibn Zubair! Refrain from deviation in the sanctuary of Allah, for I heard the Messenger of Allah (peace and blessings be upon him) say: "Soon, a man from the Quraysh will violate the sanctity of the House of Allah. If his sins are weighed against the sins of all jinn and mankind (on a scale), his side will be heavier." Reflect upon your actions, lest you be that person.